Boron and phosphorus were implanted in p-type and n-type silicon wafers in the energy range from 0.1 to 1.5 MeV. Three different methods were used to determine the distribution of the ions: SIMS, CV and NRA. The results were fitted to a Pearson IV distribution in order to extract moments for describing the distributions analytically. The projected ranges agree well with the theoretical values. Deviations are observed at higher energies. Projected range standard deviations are significantly greater than the tabulated values. The skewness clearly deviates from available tabulated data, although the same trend is observed.